Over 100 people have been killed and numerous others injured in an explosion that rocked an illicit oil refinery in southeast Nigeria, state officials and police said Saturday.

According to reports, the fire has spread to neighboring properties.

The fire started on Friday night and immediately expanded to two fuel storage facilities at the illicit crude oil refinery, engulfing the complex in flames that quickly spread throughout the area, according to Imo State Commissioner for Information Declan Emelumba.

The immediate cause of the explosion is being probed, as is the magnitude of the deaths, injuries, and property damage, according to Emelumba.

Numerous people perished. According to Michael Abattam, the Imo State Police Command's spokesman, the deceased are all unlawful operators. The Imo state government has also proclaimed the refinery owner where the explosion happened a wanted individual, an official said.

Illegal refineries are prevalent in Nigeria, where unscrupulous business owners frequently circumvent regulations and taxes by establishing refineries in isolated places invisible to authorities. Okenze Onyenwoke, the alleged operator of the unauthorized refinery, is still at large.

The practice is so pervasive that it hurts Nigeria's crude oil production in the oil-rich Niger Delta region. Nigeria is Africa's most significant crude oil production, but it lacks refineries, necessitating the importation of most gasoline and other fuels.